For the curd lattice cake, prepare an oil cake from eggs, powdered sugar, vanilla sugar, lemon zest, salt, oil, water, flour and baking powder. Tip: stir until very foamy.
For the curd mixture, blend curd, confectioners’ sugar, eggs, vanilla sugar and lemon zest in a food processor until a fine mixture forms.
Spread the dough on a baking sheet, pour the curd mixture into a piping bag and draw grid-like lines on the dough with the mixture.